[Touchdown67]

Originally Posted by 1963c-10

Jack up the back of the truck and remove the rear diff cover. Count the # of teeth on the ring gear, count the number of teeth on the pinion. Divide the ring gear # by the pinion gear # and you have the rearend ration. Example: a ring gear with 39 teeth and a pinion with 10 will give you a 3.90 ratio.

Thanks for the info..